Use of Statistics in Medical Malpractice (and Other) Trials

Defendants in medical negligence cases try to argue that, say, because a bowel is perforated in 15 in 10,000 cases of a certain surgery it was not negligent to perforate the bowel in the subject surgery.

The Supreme Court of Virginia just ruled that that evidence could not be introduced and that that argument could not be made.

Take a look as this excerpt from the opinion: “That argument, and the statistical evidence on which it was based, had nothing to do with the issue of mitigation of damages. … Further, the argument was based upon a premise unsupported by the evidence: That perforations are just as likely to occur in the absence of negligence as in its presence. The statistical evidence was so misleading that, for all the jury could determine, each of the perforations of the colon contained in the statistics may have been due to a physician’s negligence. In that event, the jury could infer the direct opposite of defense counsel’s argument: That perforations occur only where the physician is negligent. See McCloud v. Commonwealth, 269 Va. 242, 259, 609 S.E.2d 16, 25 (2005) (evidence of a raw number of events, without describing their circumstances, can be misleading or confusing to the jury); Sanitary Grocery Co. v. Steinbrecher, 183 Va. 495, 499-500, 32 S.E.2d 685, 686-87 (1945) (evidence that 1,000 customers per day visited grocery store without injury inadmissible as misleading and throwing no light upon the facts of the case before the jury). We conclude that such raw statistical evidence is not probative of any issue in a medical malpractice case and should not be admitted.”

As the above opinion indicates, the use of statistical evidence is an issue in other types of personal injury and wrongful death cases, too.